The present invention relates to a guide assembly which is of the type having a plurality of foldable fins for projectiles and missiles. More particularly, the present invention relates to a guide assembly having a plurality of fins which are foldable and unfoldable in the circumferential direction and wherein each fin comprises two fin blades whose tips are connected with one another and whose roots are fastened to separate bearings, which are mounted on the guide assembly and whose circumferential spacing is variable in such a manner that, in the unfolded state of the fins, the fin blades are arranged in the manner of a peaked roof, and the bearings are composed of an articulated fixed bearing and an articulated slide guide bearing, with the slide guide bearing being disposed so as to move in a groove.
Such guide assemblies, which are employed particularly for secondary ammunition elements ejected from carrier projectiles over the target area, are disclosed, for example, in International patent publication No. WO 84/02154 (international Ser. No. PCT/EP085/00452). In order for all of the fin blades to have the same length when unfolded and to be arranged in symmetry, the slide bearing in these prior art guide assemblies is of such construction that it is interrupted in its center region to accommodate the fin root of the second fin blade with its fixed bearing when the fins are collapsed or folded. When seen in the axial direction of the projectile or missile, the fixed bearing and the slide bearing thus are congruent, i.e., coaxial, in the collapsed state of the fin. The drawback of such a structure is primarily the complicated and expensive configuration of the bearings.
British patent No. 745,252 discloses a guide assembly in which the fixed bearing and the slide guide bearing are arranged one behind the other, i.e., adjacent, when seen in the circumferential direction of the missile, when the fin is in the folded or collapsed state. The sliding movement of the slide guide bearing during unfolding of the fins blades occurs concentrically with the center or longitudinal axis of the missile. The drawback of such a guide assembly is the fact that after the fin blades have unfolded, they are inclined toward one side and therefore have different stability depending on which side is exposed to the force of the wind.
U.S. Pat. No. 3,103,886 discloses a guide assembly for projectiles in which the two fin blades are each connected with a slide guide bearing and relatively complicated pressure members are additionally required to unfold the fins.